The immunogenic properties of plasmid DNA and recombinant adenovirus (Ad) encoding the carcinoembryonic antigen (CEA) were examined in mice by measuring both the amplitude and type of immune response, and the immunogenicity of codon usage optimized cDNA encoding CEA (CEAopt) was assessed both in C57Bl/6 and CEA transgenic mice. Vectors were injected into quadriceps muscle either alone or in combination, and plasmid DNA was electroporated to enhance gene expression efficiency and immunogenicity. Injection of plasmid pVIJ/CEA followed by Ad-CEA boost elicited the highest amplitude of both CD4 1 and CD8 1 T-cell response to the target antigen, measured by both IFNc-ELIspot assay and intracellular staining. Vectors carrying cDNA of CEAopt expressed a greater amount of the CEA protein than their wild-type counterparts, and this enhanced expression was associated with greater immunogenicity. Both CD4 1 and CD8 1 T-cell epitopes were mapped in the C-terminal portion of the protein. In CEA transgenic mice, only immunization based on repeated injections of pVIJ/ CEAopt followed by Ad-CEAopt was able to elicit a CEA-specific CD8 1 T-cell response, whereas the wild-type vectors did not break tolerance to this target antigen. MC38-CEA tumor cells injected s.c. in CEA transgenic mice vaccinated with CEAopt vectors exhibited delayed growth kinetics. These studies demonstrate that this type of genetic vaccine is highly immunogenic and can break tolerance to CEA tumor antigen in CEA transgenic mice. ' 2005 Wiley-Liss, Inc.Key words: CEA; DNA electroporation; adenovirus Despite improvements in prevention, early detection and treatment, the possibility of curing many cancer patients remains elusive. Thus, cancer continues to be a largely unmet medical need for which more efficient therapeutic strategies must be developed. 1 Particular attention has been given to active specific immunotherapy of cancer, whereby patients are immunized against antigens presented by tumor cells. In fact, experimental and clinical evidence have demonstrated the critical role played by the cellular and humoral responses in controlling tumor growth and metastasis. 2 Many of these therapies are specifically targeted to tumorassociated antigens among which carcinoembryonic antigen (CEA) is a frequent example due to its ectopic and deregulated expression in a large percentage of adenocarcinomas. 3 Human CEA is the prototypic member of the human CEA family, a group of highly glycosylated homotypic/heterotypic cell surface intracellular adhesion molecules, and part of the immunoglobulin gene superfamily. CEA is widely used as human tumor marker, is expressed mostly in the gastrointestinal tract and is overexpressed in many human cancers, including epithelial tumors originating from the gastrointestinal tract, lung, thyroid, breast, prostate, cervix and ovaries. 4 CEA has been the focus of extensive preclinical and clinical investigation aimed at developing a CEA-specific vaccine with a therapeutic impact on tumor progression. 5 In this context, genetic vacc...

Myeloid-derived suppressor cells (MDSC) include immature monocytic (M-MDSC) and granulocytic (PMN-MDSC) cells that share the ability to suppress adaptive immunity and hinder the effectiveness of anti-cancer treatments. Of note, in response to interferon-γ (IFNγ) M-MDSC release the tumor-promoting and immunosuppressive molecule nitric oxide (NO), whereas macrophages largely express anti-tumor properties. Investigating these opposing activities, we found that tumor-derived prostaglandin E2 (PGE2) induces nuclear accumulation of p50 NF-κB in M-MDSC, diverting their response to IFNγ towards NO-mediated immunosuppression and reducing TNFα expression. At the genome level, p50 NF-κB promoted binding of STAT1 to regulatory Research.

In this account, we report the development of a series of substituted cinnamic anilides that represents a novel class of mitochondrial permeability transition pore (mPTP) inhibitors. Initial class expansion led to the establishment of the basic structural requirements for activity and to the identification of derivatives with inhibitory potency higher than that of the standard inhibitor cyclosporine-A (CsA). These compounds can inhibit mPTP opening in response to several stimuli including calcium overload, oxidative stress, and thiol cross-linkers. The activity of the cinnamic anilide mPTP inhibitors turned out to be additive with that of CsA, suggesting for these inhibitors a molecular target different from cyclophylin-D. In vitro and in vivo data are presented for (E)-3-(4-fluoro-3-hydroxy-phenyl)-N-naphthalen-1-yl-acrylamide 22, one of the most interesting compounds in this series, able to attenuate opening of the mPTP and limit reperfusion injury in a rabbit model of acute myocardial infarction.

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